Harrasment

Hi my father is 63yrs and my mother 60 yrs. My done property in the name of my mother but he has taken money from others due to financial problem so my is afraid to go near that property as he has iou has to paid they will harass him. Currently me daughter main earner looking after my parents. But my father is a saddist from the day he married to my mother till now he is harrassing. Mother suffering from high BP so now she cant bear that physical violence or harassment. I am still single worried about my mother trying to protect her from this person. Now he torturing my mother to give his property back to him. My mother is ready to give property but he forcing her sign in power of atorny so that he can show that papers to buyer get some advance and ranaway. I have given a police complaint regarding but police is saying they dont have rights to arrest or force him to leave house. Currently i am staying in rent house i paying rent security deposit but he is ready move out from house. After selling house he is not ready to pay to them from whom he borrowed money.Everything he wants put on my mother .please suggest wat action can be taken on him.